Faculty Bibliography

The primary objective of this article was to critically evaluate the routine use of confirmatory factor analysis (CFA) for representing an individual's performance across a battery of executive function tasks. A conceptual review and statistical reanalysis of N = 10 studies that used CFA methods of EF tasks was undertaken. Despite evidence of excellent global model fit for CFA models, studies were uniformly characterized by weak correlations among EF tasks and weak to moderate levels of maximal reliability of latent EF constructs. Vanishing tetrad tests raised the possibility that individual tasks may be better conceptualized as causal rather than as effect indicators of the latent construct of EF. The use of CFA methods with EF tasks that are weakly correlated results in latent variables that have poor to modest maximal reliability. This undermines efforts to use latent variables of EF as predictors or outcomes in empirical studies and has implications for theory development. Greater attention to and resolution of the discrepancies between conceptual definitions and statistical approaches that are used to model EF has implications for the long-term value of using EF in research and clinical settings. © Taylor & Francis Group, LLC.

The current study was designed to test hypotheses derived from an ecological framework regarding the association between perceived racial discrimination and maternal emotion talk among a sample of 415 African American mothers living in the rural South. Mothers reported on experiences with racial discrimination when her child was 24 months old. Additionally, maternal emotion awareness was assessed by mothers"™ use of emotion words during an emotion-laden picture book interaction with her young child. Hierarchical regression analysis revealed that mothers"™ perception of racism was a significant positive predictor of mothers"™ emotion words, even after controlling for a variety of distal demographics and maternal and child characteristics. However, this main effect was qualified by significant interactions. Specifically, the strength of the association between perceived discrimination and mothers"™ emotion words was reduced in the presence of maternal psychological supports, including greater life satisfaction and knowledge of child development.

This study examined whether a minimum level of preschool quality (threshold) is needed in order for a relationship to exist between preschool quality and children's academic, behavioral, and working memory in a sample of children from low-wealth rural communities where quality child care has been found to be lower than more urban communities. Participants included 849 children from two high-poverty, rural regions. Preschool quality was rated using the CLASS observational measure. Child outcomes included direct assessments of early language, mathematics, and working memory, as well as teacher ratings of attention, emotion regulation, problem behaviors, and peer relationships. Analyses included piecewise regression analyses that tested a priori specified cut-points and flexible b-spline analyses that tested for thresholds empirically. Results indicated some evidence for quality thresholds, suggesting that quality was related to children's behavioral outcomes above, but not below, a cut-point. Language, literacy, and working memory did not show evidence of threshold effects. Results are discussed in the context of prior mixed evidence for child care quality thresholds in other samples of predominantly low-income preschoolers in center-based child care in more urban areas.

BACKGROUND: Hyperuricemia is associated with multiple diseases, including gout, cardiovascular disease, and renal disease. Serum urate is highly heritable, yet association studies of single nucleotide polymorphisms (SNPs) and serum uric acid explain a small fraction of the heritability. Whether copy number polymorphisms (CNPs) contribute to uric acid levels is unknown. RESULTS: We assessed copy number on a genome-wide scale among 8,411 individuals of European ancestry (EA) who participated in the Atherosclerosis Risk in Communities (ARIC) study. CNPs upstream of the urate transporter SLC2A9 on chromosome 4p16.1 are associated with uric acid (chi2df2=3545, p=3.19x10-23). Effect sizes, expressed as the percentage change in uric acid per deleted copy, are most pronounced among women (3.974.935.87 [ 2.55097.5 denoting percentiles], p=4.57x10-23) and independent of previously reported SNPs in SLC2A9 as assessed by SNP and CNP regression models and the phasing SNP and CNP haplotypes (chi2df2=3190,p=7.23x10-08). Our finding is replicated in the Framingham Heart Study (FHS), where the effect size estimated from 4,089 women is comparable to ARIC in direction and magnitude (1.414.707.88, p=5.46x10-03). CONCLUSIONS: This is the first study to characterize CNPs in ARIC and the first genome-wide analysis of CNPs and uric acid. Our findings suggests a novel, non-coding regulatory mechanism for SLC2A9-mediated modulation of serum uric acid, and detail a bioinformatic approach for assessing the contribution of CNPs to heritable traits in large population-based studies where technical sources of variation are substantial.

The identification of phenotypic associations in high-dimensional brain connectivity data represents the next frontier in the neuroimaging connectomics era. Exploration of brain-phenotype relationships remains limited by statistical approaches that are computationally intensive, depend on a priori hypotheses, or require stringent correction for multiple comparisons. Here, we propose a computationally efficient, data-driven technique for connectome-wide association studies (CWAS) that provides a comprehensive voxel-wise survey of brain-behavior relationships across the connectome; the approach identifies voxels whose whole-brain connectivity patterns vary significantly with a phenotypic variable. Using resting state fMRI data, we demonstrate the utility of our analytic framework by identifying significant connectivity-phenotype relationships for full-scale IQ and assessing their overlap with existent neuroimaging findings, as synthesized by openly available automated meta-analysis (www.neurosynth.org). The results appeared to be robust to the removal of nuisance covariates (i.e., mean connectivity, global signal, and motion) and varying brain resolution (i.e., voxelwise results are highly similar to results using 800 parcellations). We show that CWAS findings can be used to guide subsequent seed-based correlation analyses. Finally, we demonstrate the applicability of the approach by examining CWAS for three additional datasets, each encompassing a distinct phenotypic variable: neurotypical development, Attention-Deficit/Hyperactivity Disorder diagnostic status, and L-DOPA pharmacological manipulation. For each phenotype, our approach to CWAS identified distinct connectome-wide association profiles, not previously attainable in a single study utilizing traditional univariate approaches. As a computationally efficient, extensible, and scalable method, our CWAS framework can accelerate the discovery of brain-behavior relationships in the connectome.

The influence of perceived family conflict, family support, and peer substance use on adolescent substance use was examined in a community sample of 669 (331 female, 338 male) Latino youth, who were assessed twice over the span of 21/2 years. We found greater substance use among U.S.-born Latino youth in comparison to foreign-born Latino youth at both time points. Levels of family conflict were higher, and levels of family support were lower, in families with U.S.-born versus foreign-born adolescents. Results suggest that higher family conflict, but not lower family support, may partially explain higher substance use rates among U.S.-born versus foreign-born Latino adolescents.